The present invention is more particularly related to removal of petroleum hydrocarbons from contaminated soil or dirt which is found at or adjacent to gasoline storage tanks, gasoline pumps, and other areas where petroleum products have impregnated the ground. The invention is also useful for removal of hazardous and non-hazardous solvents, and volatile and semi-volatile organic compounds from soil, including, without limitation, toluene, ethanol, phenols, and chlorinated solvents.
It has been estimated that there are more than 120,000 gasoline service stations in the United States, each of which may have gasoline or other petroleum products spilled or discharged or leaked into the soil around such service stations. In addition, there are many thousands of other automotive repair shops and users of petroleum products which are equally subject to having had petroleum contaminants spilled or leaking into the soil during the many years which there was no attention to protection of the environment. In a recent Wall Street Journal article, it was reported that a high percentage of gasoline storage tanks are currently leaking, and these spills must be dealt with in the future. Whenever an area that has been contaminated by petroleum products is sold, or a new use of that area is begun, the Environmental Protective Agency, or its state equivalent, requires that all contaminated soil be removed and/or sanitized. This is currently a difficult and costly procedure.